How can I have one layout for landscape and one for portrait? I want to assume extra width and conserve vertical space when the user rotates the phone over sideways.
I will try to explain it shortly.
First, you may notice that now you should use ConstraintLayout as requested by google (see androix library).
In your android studio projet, you can provide screen-specific layouts by creating additional res/layout/ directories. One for each screen configuration that requires a different layout.
This means you have to use the directory qualifier in both cases :
As a result, here is an exemple :
res/layout/main_activity.xml # For handsets
res/layout-land/main_activity.xml # For handsets in landscape
res/layout-sw600dp/main_activity.xml # For 7” tablets
res/layout-sw600dp-land/main_activity.xml # For 7” tablets in landscape
You can also use qualifier with res ressources files using dimens.xml.
res/values/dimens.xml # For handsets
res/values-land/dimens.xml # For handsets in landscape
res/values-sw600dp/dimens.xml # For 7” tablets
res/values/dimens.xml
70dp
res/values-land/dimens.xml
150dp
your_item_grid_or_list_layout.xml
Source : https://developer.android.com/training/multiscreen/screensizes